Delay action switch



Oct, 22, 1957 A. N GULNICK DELAY ACTION SWITCH 2 Sheets-Sheet 1 FiledApril 11, 1955 INVENTOR ADR/O/V /V. GUZ/V/Ck ATTORNEY Oct. 22, 1957 A.N. GULNICK 1 DELAY ACTION SWITCH Filed April 11, 1955 2 Sheets-Sheet 2INVENTOR AD/Q/OA/ /v. cum/c United States Patent 2,810,797 DELAY ACTIONSWITCH 'A' drio'n N. 'Gulnick, Palisades Park, N. J., assignor toInternational Telephone and Telegraph Corporation, 'Nutley, N. J., acorporation of Maryland My invention relates to a delay action switchand is more particularly directed to the utilization thereof inconnection with a generator of the type used to produce ringing currentat a telephone subscribers set or to control the switching action of arelay or other spring pileup contact assemblies.

In generators of this type, it is usual to provide a switch to connectthe generator to the line and to disconnect the telephone set, when aringing signal is transmitted. Switches of this type, heretofore known,are actuated by centrifugal action and are relatively costly tomanufacture and maintain. Furthermore it has been found undesirable tohave the switching operation dependent upon the rotational speed of thegenerator.

An object of my invention is to provide a switching device having adelay characteristic which is relatively simple to construct and easy tomaintain.

Anotherobject of my invention is to provide a generator switch which isactuated independent of the rotational speed of the generator.

One of the features of the invention is the provision of a suction cupdevice carried by a moving part of the switch. This cup is pressed intosuction engagement with a given surface upon actuation of the switch atthe instant I the drive shaft is turned. The switch remains in thisact-uatedposition for a certain time after termination of the switchactuating force. The time delay may be adjusted according torequirements by a needle valve associated with suction cup.

Further objects and features of my invention will become more apparentby reference to the following description and the accompanying drawings,wherein:

Fig. 1 is an elevational view partially in section taken along the line1--1 of Fig. 2 showing the switching device in a non-operated position;

Fig. 2 is plan view taken along the line 2-2 of Fig. 1 illustrating theswitching device;

Fig. 3 is an elevational view partially in section taken along the line11 of Fig. 2, with the switching device in operated position;

Fig. 4 is a view in perspective of the switching device;

Figs. '5 and 6 are schematic developments of a camclutch which actuatesthe switching device; and,

Fig. 7 is a sectional view of a valve used to control the delay requiredof the switch.

With reference to the drawings, the delayed action switch of myinvention is illustrated in combination with a telephone ringinggenerator. The switch, for example, is shown mounted within asubstantial cylindrical moisture-proof shell comprising housing elements1, 2, and 3. The element 1 is an end closure adapted to be mounted on apanel 4 by a mounting nut 5. The housing element 2 is joined to the endelement 3 by a retaining ring 6. The end element 3 contains the rotorand stator and the element 2 contains the drive mechanism, the detailedinformation of which may be had by reference to copending applicationsof O. C. From, L. B. Haigh and A. N. Gulnick, Serial No. 496,674, filed2,810,797 Patented Oct. 22, 1957 March 25, 1955, and G. F. McCarthy andA. N. Gulnick, Serial No. 500,506, filed April 11, 1955, respectively.

A drive shaft 7 extends into the housing, from a drive handle 8. Acam-clutch device is mounted on the drive shaft 7 comprising a firstpart 9 carried by the shaft 7 and a second part 10 rotatably and axiallymoveable on the shaft. Parts 9' and 10 are biased against each other byrestoring spring 11.

Figs. 5 and 6 illustrate a schematic development of the cam-clutch.Parts 9 and 10 are formed into annular elements having complementaryU-shaped portions 12 and 13 and complementary V-shaped portions 14 and15. The U shaped portions 12 are larger than portions 13 to provide alimited rotational movement during which the cam portions 14 and 15cause the part 10 to move axially to actuate switching device 16, intoan operated position shown in Fig. 3. The cam-clutch is returned upontermination of shaft movement to the normal position by the restoringspring 11 and the V shaped portions 14 and 15.

A transfer switch assembly 16, Fig. 4, comprises an arcuate frame 1601which carries a spring leaf 17 having a make contact 17a, a spring leaf18 having a break contact 18a and a transfer contact spring 19. Thetransfer spring 19 is equipped with a retarding device comprising asuction cup 20 having a needle valve 21 shown in enlarged detail in Fig.7.

It may be seen from the above description that rotation of the driveshaft in either direction will move cam portion 10 axially intoengagement with element 19a to actuate the transfer spring 19 to firstopen the break contact 18a, thereby disconnecting the substationcircuits from the line, and next to close with make contact 17a, therebyconnecting the generator output to the line. The cup 20 is also broughtinto suction engagement with the sealing plate 22.

Termination of the crank rotation permits the cam clutch to return tothe normal non-actuating position, by means of the restoring spring 11and the V-shaped portions 14 and 15. The suction cup 20, however,maintains the transfer spring 19 in the actuated position for a shortinterval of time, to permit the ringing voltage on the line to dissipatethrough the generator. The delay action of the switch may be adjustedaccording to requirements by the needle valve 21 contained in thesuction cup 20. As shown in Fig. 7, the valve 21 is threadably receivedin valve body 23 onto which the resilient cup portion is secured. Thethreaded portion of the needle valve 21 has a groove 24 whereby apassageway is provided from between the interior and exterior of thecup, the passageway being controlled by the adjustment of the needlevalve 21. After a predetermined time, depending upon adjustment of valve21, the suction cup releases its grip on the surface 22 and the transferspring 19 is restored to its normal position, thereby disconnecting thegenerator from the line and re-establishing the circuit for thetelephone set by closing with break contact 13a. When the switch is inthis normal position, the spacer 25 holds the leaf 17 and its contact17a properly spaced from the transfer spring 19.

From the foregoing description it will be clear that I have provided animproved delayed action generator switch, having a delay actionindependent of the rotational speed of the generator. It will also beapparent that the switch structure is relatively easy to manufacture andto assemble with other parts of the generator and furthermore, that thedelay action may easily be adjusted according to requirements.

While I have shown and described the switch in combination with agenerator, it will be obvious to those skilled in the art that it may beapplied to many switching devices where a delayed action is desired,either when the transfer spring is actuated or released. The suction cupmay be used to control the contact operation of various relays andvarious spring assemblies. Still other applications are possible withcontact pile-up assemblies actuated by means other than relays orrotating shafts.

While I have described above the principles of my invention inconnection with specific apparatus, it is to be clearly understood thatthis descripion is made only by way of example and not as a limitationto the scope of my invention.

I claim:

1. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a signalling current is desired, atransfer switch having break, make and transfer contacts, meansresponsive to initial rotation of said shaft to actuate said transfercontact to disengage said break contact and to engage said make contact,and to maintain the transfer contact in actuation throughout therotation of said shaft, and retarding means operative upon terminationof shaft movement to delay for a predetermined interval the returnmovement of said transfer contact.

in a telephone signalling generator having a drive shaft adapted to berotated one or more times when a signalling current is desired, atransfer switch having break, make and transfer contacts, a cam deviceresponsive to initial rotation of said shaft to actuate said transfercontact to disengage said break contact and to engage said make contact,and to maintain the transfer contact in actuation throughout therotation of said shaft, and retarding means operative upon terminationof shaft movement to delay for a predetermined interval the returnmovement of said transfer contact.

3. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a signalling current is desired, atransfer switch having break, make and transfer contacts, meansresponsive to initial rotation of said shaft to actuate said transfercontact to disengage said break contact and to engage said make contact,and to maintain the transfer contact in actuation throughout therotation of said shaft, and retarding means coupled to said transfercontact, said retarding means being operative upon termination of shaftmovement to delay the return movement of said transfer contact, saidretarding means being adjustable to selectively determine the delayinterval.

4. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a sig nalling current is desired, atransfer switch comprising a first element having a break contact, asecond element having a make contact, a third element having transfercontacts disposed for co-action with said break and make contacts, amotion retarding device coupled to said third element adapted to beactuated into a retarding position by a movement of said third element,means responsive to initial rotation of said shaft to move said thirdelement to effect disengagement of said transfer contacts with respectto said break contact and engagement with respect to said make contactand to cause said device to assume a retarding position, and to maintainthe transfer contact in engagement with said make contact and saiddevice in retarding position throughout the rotation of said shaft, saiddevice operating to retard the return movement of said third element toeffect a delayed switching action upon termination of shaft movement.

5. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a signalling current is desired, atransfer switch comprising a first element having a break contact, asecond element having a make contact, a third element of resilientcharacter having transfer contacts disposed for co-action with saidbreak and make contacts, the resilient character of said third elementoperating to normally bias said transfer andbreak contacts inengagement, a plate, a suction cup coupled to said third element adaptedto be pressed into suction engagement with said plate, means responsiveto initial rotation of said shaft to move said third element to effectdisengagement with respect to said break contact and engagement withrespect to said make con tact and to cause said suction cup to bepressed against said plate, and to maintain the third element engagedwith respect to said make contact and said suction cup pressed againstsaid plate throughout the rotation of said shaft.

6. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a signalling current is desired, atransfer switch comprising a first element having a break contact, asecond element having a make contact, a third element of spring materialhaving transfer contacts disposed for co-action with said break and makecontacts, said third element being disposed so that the resiliencethereof normally biased the transfer contact thereof in engagement withsaid break contact, a suction cup coupled to said third element andadapted to be pressed into suction engagement with a given surface,means responsive to initial rotation of said shaft to move said thirdelement to effect disengagement with respect to said break contact andengagement with respect to said make contact and to cause said suctioncup to be pressed against said surface, and to maintain the thirdelement engaged with respect to said make contact and said suction cuppressed against said plate throughout the rotation of said shaft, saidsuction cup having a passageway between the interior and exteriorthereof and a valve adjustable to control the degree of opening of saidpassageway.

7. In a telephone signalling generator having a drive shaft adapted tobe rotated one or more times when a signalling current is desired, asupport, a first element having a break contact, a second element havinga make contact, a third element having a transfer contact, said first,second and third elements being supported by said support with thecontacts thereof disposed for coactive operation, said transfer andbreak contacts being normally biased toward engagement, a suction cupcarried by said third element, means responsive to initial rotation ofsaid shaft to move said third element for disengagement between saidbreak and transfer contacts, for engagement between said transfer andmake contacts and to press said suction cup against an adjacent surfaceto effect suction action, and to maintain the third element engaged withrespect to said make contact and said suction cup pressed against saidplate throughout the rotation of said shaft, whereby said suction cupretards the return of said third element to normal position upontermination of shaft movement.

References Cited in the file of this patent UNITED STATES PATENTS2,313,064 Hall Mar. 9, 1943 2,394,712 Mudon Feb. 12, 1946 2,550,889Tyler May 1, 1951 FOREIGN PATENTS 274,070 Switzerland June 16, 1951768,719 France May 28, 1934

